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I have done the IF can rebuild and removed the mica sheets and trimmed the contacts inside the cans and added black tape to prevent shorts. I then added a 22 pf cap on the bottom of the chassis across the terminals to the FM IF's and 4, 22 pfs giving 88 pf on the AM if's (100 may be the ideal value for AM) and it tuned up just fine and gave good peformance.
To troubleshoot the suspect set I would put it on an isolation transformer (you can make one from 2, 110-12 volt transformers, connect 12 volt windings together, one 110 volt winding is input, other output).
You've got to use an iso trans to avoid hot chassis shock hazard.
Then take portable radio or cassette player headphone output, ground to isolated chassis, hot lead through .047/600 v cap. This is the test signal source, apply to volume control, output tube grid etc and see if you're getting signal flow.
Also check out all power supply voltages.
Last edited by Chad Hauris; 10-31-2005 at 11:22 PM.
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